                                                "Exiting..."              ))
 (defmacro ERR-SRV-PORT-IS-IN-USE        [](str "due to the port requested "
                                                "is in use. Exiting..."   ))
+(defmacro ERR-COULD-NOT-LOOKUP          [] "could not lookup hostname"    )
 
 ; Print this error message when there are no any args passed.
 (defmacro ERR-MUST-BE-ONE-TWO-ARGS-1 [](str ": There must be one or two args "

(defmacro HDR-PRAGMA-N            [] "pragma"                       )
(defmacro HDR-PRAGMA-V            [] "no-cache"                     )
(defmacro RSC-HTTP-200-OK         [] 200                            )

; Daemon name, version, and copyright banners.
(defmacro DMN-NAME        [] "DNS Resolver Daemon (dnsresolvd)"       )

(defmacro DIGITS           [] #"\d+")
(defmacro PARAMS-SEPS      [] #"=|&")

; JSON entities :-).
(defmacro CB1 []   "{\"")
(defmacro CB2 []   "\"}")
(defmacro DQ1 [] "\":\"")
(defmacro DQ2 [] "\",\"")

; Common error messages.
(defmacro ERR-PREFIX                    [] "error"                        )
(defmacro ERR-PORT-MUST-BE-POSITIVE-INT [](str ": <port_number> must be "
